Follicular lymphoma (FL) is the second most common non-Hodgkin's lymphoma. Several treatment options exist today, but these are costly and include significant toxicities. No biological or genetic markers are available in clinical practice for reliable risk stratification of follicular lymphomas and the choice of appropriate treatment depends heavily on morphology-based histological grading. In a system adopted by the World Health Organization (WHO), follicular lymphomas are stratified into three grades depending on the average count of centroblasts in ten randomly selected, standard high-power fields (HPFs). Follicular lymphomas with low histological grades show an indolent clinical course with long average survival, but are considered incurable with currently available therapies. In contrast, high-grade follicular lymphomas have an aggressive clinical course and are rapidly fatal if not treated with aggressive chemotherapy. However, in contrast to low-grade follicular lymphoma, high-grade FL may be cured with aggressive chemotherapy. Currently, the inter-reader agreement between pathologists in grading FL is extremely low. In a multi-site study, the agreement among experts for the various grades of follicular lymphoma varied between 61% and 73%. Since only ten HPFs are used by the pathologist for practical reasons, this system may be prone to selection bias in cases that show significant differences in various areas of a section. The primary goal of this project is to develop an effective computer-aided system to assist pathologists in making diagnostic decisions about histological grading of follicular lymphoma. It is important to note that this project aims to provide supplementary information to the pathologist as he or she carries out the classification process;this is not an attempt to automate the classification process. To achieve this objective, ten board-certified hematopathologists (with experience in grading follicular lymphoma) from The Ohio State University, Cleveland Clinic, Vanderbilt University, and private practice will participate in the creation of the database that will contain digitized follicular lymphoma slide images, as well as the associated truth for the development and evaluation of the computer-aided follicular lymphoma grading system. After extensive evaluation of the system with the collected datasets and outcome data, as well as datasets from the Cancer and Leukemia Group B (CALGB) trials, the developed system will be installed at participating pathologists'institutions, and the developed software will be made available to the research community as a shareable resource. PUBLIC HEALTH RELEVANCE: Follicular lymphoma (FL) is the second most common non-Hodgkin's lymphoma. This project aims to provide supplementary information to the pathologist for the grading of the tumor using computerized image analysis techniques. The supplementary information will be useful for better diagnosis, prognosis and treatment of this disease.